CDM) Sergio Busquets
Now this one may seem more outlandish, but if the midfielder is on the market then the Red Devils should move very quickly. According to the Mirror he is, and United are keen.
The Spaniard would be the perfect player to allow the team’s attacking players to flourish, exactly like he has done at FC Barcelona for years now. Whether or not it is actually feasible is another matter, but if it is he would be an amazing signing.